The lack of variability of the broad iron line seen in the Seyfert 1 galaxy MCG–6-30-15 is studied using the EPIC pn data obtained from a 2001 observation of 325 ks, during which the count rate from the source varied by a factor of 5. The spectrum of 80 ks of data from when the source was bright, using the the lowest 10 ks as background, is well fitted over the 3–10 keV band with a simple power...

An electro-optic silicon modulator with negative electrical power dissipation is proposed. The device performs optical modulation through electrical control of losses caused by two photon absorption. It further exploits the nonlinear photovoltaic effect to recover the optical power that is normally dissipated when the modulator is in the on state.

An overview of clocking and design of clocked storage elements is presented. Systematic design of Flip-Flop is explained as well as “time borrowing” and absorption of clock uncertainties. We show how should different clocked storage elements be compared against each other. The issues related to power consumption and low-power design are presented.

We report the highly efficient continuous-wave diode-pumped laser operation of Er, Yb:GdAl3(BO3)4 crystal. Absorption and stimulated emission spectra, emission lifetimes, and efficiencies of energy transfer from Yb3+ to Er3+ ions were determined. A maximal output power of 780 mW was obtained at 1531 nm at absorbed pump power of 4 W with slope efficiency of 26%.

We report the spectroscopy and high-power continuous-wave (CW) diode-pumped laser operation of Er:Yb:YAl3(BO3) crystal. Absorption and stimulated emission spectra, emission lifetimes, and efficiency of energy transfer from Yb3+ to Er3+ ions were determined. A CW Er:Yb:YAB laser emitting at 1602, 1555, and 1531 nm with output power as high as 1W and slope efficiency up to 35% was demonstrated.

purpose: to compare the optical properties of hydrophilic and hydrophobic intraocular lenses (iols) containing uv-absorber and to determine their chemical composition. methods: optical properties of different foldable hydrophilic and hydrophobic as well as non-foldable hydrophobic polymethylmetacrylate (pmma) iols were evaluated in three powers of 15, 22 and 25 diopters. optical properties were...

We report on the design, fabrication and optical characterization of GaN/AlN quantum-dot-based waveguides for all-optical switching via intraband absorption saturation at 1.55 µm. The transmittance of the TM-polarized light increases with the incident optical power due to the saturation of the s-p(z) intraband absorption in the QDs. Single-mode waveguides with a ridge width of 2 µm and a length...

This paper discusses the investigation of a wearable textile monopole antenna on specific absorption rate (SAR) for bodycentric wireless communication applications at 2.45 GHz. The antenna is characterized on a realistic 8 x 8 x 8 mm resolution truncated Hugo body model in CST Microwave Studio software. The result exhibited that the simulated SAR values were reduced significantly by 83.5% as th...

We present a simple measurement and analysis technique to determine the fraction of optical loss due to both radiation (scattering) and linear absorption in microphotonic components. The method is generally applicable to optical materials in which both nonlinear and linear absorption are present and requires only limited knowledge of absolute optical power levels, material parameters, and the s...